Screw driver construction



Nov. 10, 1953 G. L. ROCK scREw DRIVER CONSTRUCTION Filed April 13, '1949 1 N V EN TOR. Geo 71 c/ B Y m 1\\ will Patented Nov. 10, 1953 `SCREW DRIVER CONSTRUCTION `George L.'"R ock`, Jonesville, Mich., assignor to Vaco Products Company, Chicago, Ill., a corporation of Illinois Application April 13, 1949, Serial No. 87,319

4 claims. (c1. 27s-ass) This invention relates to a hand tool of the type having a handle and a work piece, and more particularly to a screw driver or the like having a detachable bit.

In order to save space in storage and to make it unnecessary to invest in a large number of duplicate parts, screw drivers or the like are frequently made with detachable bits so that a single handle may beused with any one of a plurality of bits which maybe either single or double ended. Prior detachable bit screw driv-l ers fall into one of two general classes: those in which the bit and handle are connectible or disconnectible by relative longitudinal movementand those which require other movements such as transverse or rotative in addition to longitudinal movement. The former, because of the ease or operation, is greatly to be preferred and is the type with which the current invention is concerned. f e

AIt has been common practice heretofore in separable bit screw drivers of the class with which this invention is concerned to provide the bit with an enlarged body portion of a shape such as hexagonal to resist relative rotation between the handle and the bit, the body portion `being cooperable with a longitudinally apertured sleeve carried by the handle. A transverse aperture has been provided in the body portion o f the bit containing a coil spring biasing a ball radially outward, the aperture having had a narrow neck to restrict the movement of the ball. One or more cooperating indents has been provided in the sleeve portion to receive the ball and thus resist longitudinal movementbetween the handle and bit.

Certain disadvantages attend the construction just described. Screw driver bits are generally of fairly small diameter and may be readily formed from bar stock. It is generally impossible to incorporate a ball and spring in the relatively small shank of a screw driver vbit unless it is i provided with an enlarged section such as the hexagonal body portion previously referred to, and such an enlarged section makes it diiicult or impossible to manufacture a bit from bar stock. Likewise the sleeve is generally not thick enough to accommodate a ball and spring to force the ball against an indent in the shank of the bit. Furthermore, dirt enters the aperture around the ball and eventually becomes so tightly packed as to prevent movement of the ball. As there is no Way of removing dirt from behind the ball, the bit is then useless.

Among the important objects of this invention is the provision of a tool handle and work piece separable by a relative longitudinal motion in which it is unnecessary to provide an enlarged portion on the shank of the work piece.

It is another object of this invention to provide a hand tool such as a screw driver having a handle and work piece or bit detachably connectable by longitudinal motion having resiliently biased transversely movable latching means which are exposed and may be readily cleaned.

Other and further objects and advantages of the instant invention Will be apparent from the following description When taken in conjunction with the accompanying drawings in which:

Figure 1 is a side view of a detachable bit screw driverembodying the present invention;

Figure 2 is a longitudinal cross sectional view of the screw driver shown in Figure 1;

Figure 3 is a perspective view of a detachable bit and cooperating locking sleeve;

Figure 4 is an enlarged fragmentary sectional view taken along the line 4-5 in Figure 2;

Figure 5 is a sectional view taken along the line 5-5 in Figure 4;

Figure 6 is a cross sectional view taken along the line li-S in Figure 2;A and -Figure 7 shows theportion or the hit shank shown in Figure 5 when the sameis removed from therefrom.VH The bit is shown as double ended.,

having a conventional screw driver blade 5 and a four-pronged driver I for cross-slotted screws. It is to be understood, however, that the bit could be single ended if desired and could include other types of drivers, such as clutch head drivers, socket type drivers, etc. At a convenient location which in the present embodiment is substantially midway between the ends of the bit, a portion of the shank' 9 of the bit is iiattened to produce a pair of radial flanges II and consequent indented portions I3. An aperture I5 is provided substantially perpendicular to and at the center of the flattened portion of the shank 9. .A leaf spring l'I has its end portions I9 lying within small recesses 2| at opposite longitudinal extremities of one of the indents I3. The spring Il has an aperture 23 at its center aligned with the aperture I5 and an oval head pin 25 is passed through the two apertures with the oval head adjacent the spring. The other end is peened over as at 21 to retain portions of spring I 9 3 under slight tension within recesses 2l. The movement of pin 25 in one direction is limited when the peened end of pin 25 abuts the surface of the indent i3, but the pin is movable in the opposite direction when the oval head is depressed against the tension of spring i1.

A sleeve 29 is secured within an axial aperture 3l in the handle; I' atfan open end thereof; and isf of a shape-suchxashexagonal to;prevent.rotationA between the sleeve and the handle. The sleeve 29 is provided with a longitudinal slot 33 on eacm side of an axial bore 35 and the ianges.V Ll. l. Within the slots as the shank 9 is tted within the bore 35 to prevent relativefrotatipnrof, therbit, and the sleeve. A pair of radialindents; alte provided in the inner surface of the bore 35 perpendicular to the plane of the slots. 33 to, rexlevel the head of the pin 25.

To join the handle I and bit 3, it is onlyiinecese sary to insert the end ofi' the bit which is not tobe used, shown in Egurea?.Y as thefconventionaL screw driver blade, into theraperture 35i o-tthe. sleeve. 29,` and movel the-bit.and-handle axially;4 toward each.4 other.- so that' thefflamgesV Il t.. into. theslots 3,5.. Asthe pin` 25.rea ch.esthe free-.end of; the sleeve'29which inthe iig-lires'.4 is, on, the left, it is forcedy inward toward. the indent: I3, flexing the;4 spring IJ; As; the head' of. theY pin reaches-cheery the indents'l, it is, forced intorthis indent byl the spring, to; inhibitl further. lon-r gitudinal; motion. At4 this: time;4 the innermost edges of; the-nangesf` l lY are abuttingfthe-.ends ofv the-f slots. 33; td positivelyI preclude., furtherl tele,- scopiemotionl of` the. bit.. and handle-zy In., driy.- ing or removing screws, the only axial force ulfgS.; the; bit, and handle toward one;- anotherf, and 4this is resisted by the; flanges I-l abutting,-the1 ends, of the,l slots. 35i, asY v justVV mentioned. T orsional forces are, of course, resisted-,by the; anges; LI. cooperatingV with theslots$3=` Thus thel flanges Il and slots 33: D IOvdefay coupling, betw.een,.the= bit and handle;

Very slight forces; if,anytenditoseparatefthe; bit and handle longitudinally, andthe: head` of the pin 25 pressing Within the indentsl; under,V theA inuence of thespring, l1; successfully resists such forces. If a strongpullisassertedbetween; the bit. and handle, however, the? oval headI of the pin 2,5A will, be; cammed downward; against; the influence of the spring by the complementarysurfacefof., the;` indent 3l orthe; bit; and handle and g thus; readily separate; by a., simple, long iatudinal motion.

Although for4 purposesof; illustration Irv-have; shown and, described a particular; embodiment of, myv invention; Iidoinot in t end,to.be.l limitedtheieibahut-only by the-spirit andifscooeoff. the ar-l pended i claims.`

I- claim:

11 AA, detachable bitL tool4 comprising, a; handle; having anaxial openingL at one erich. aY tool; bit, having, a4 shank; a; flangel on-,saidE shank 2r, flats tened; hert-,ion 0n: said shank.substantialh@` coter.-A minous.- withv saidf. liangei1 means inf. the,l opening 4 of said handle cooperable With said flange to couple said handle and said bit, elongated latching means extending outwardly from and substantially normal to said flattened portion of said shank, and a leaf spring bridging said flattened portion and normally urging said elongated latching means outwardly from said flattened portion.

2, Inra: detachable bit-vscrew'-driyer,` a handle hailing anaxial'. bore, a tool.bit;having ashank, a pair of radial flanges on said shank, indented portions on opposite sides of said shank cotermnous With, said flanges forming a flattened portion, said flattened portion, having an aperturef-` th.ere1ihrm1eli.,an; oval headed pin fitting lonselywithim the:.-aperture in the attened portioni andi beingf peened over to prevent detachmentmesilient. means normally biasing said pin outwardly with its head lying without the peripherylE of,v said shank, means in the bore in said handle cooperating with said flanges to couple said,- bit and said handle, andY means` complemental imshape;,to--thesheadof saidpinto inhibit longitudinalmotiorrbetween.sadhandleand.said` bit.

3,-; A, detachable bit. tool comprising a, handle havingv anaxial bore open, at. one lend, a, toolV bit. having a. shank, latching-means. carried, by. saidV shank and havingl af, camming latching, surface, resilient means normally urging. said,` latching means. tml/ard;` latcl'iing position, said resilient,

meansA disposed extern.ally;V of. said shank and. readilyV accessible, an polygonal configuration on, said shankmeans, inE said. handleA c ooperable with thepolygonal. portion off said shankV to, couple saidhandle. and'- said', bit, and, means in A saidA handle,complemental-` iny shape to the latching means ont saidrv shank` detachably toV secureA saidtool bitv in saidhand1e.`

4i tool bit, comprising., a.` Work. portion. an, elongated shank, a flattened portion.r on. said shank, saidhattenedpQrtOn. having. an .aperture therethrough, acoupling portion onsaid shank.

adjacent;4 said.A iiattenedI portion, an oval.k headed pin-V in.. saidl aperture` and extending therefrom, theendof sadpin being; neened over to. retain` saidx pirr in;A said, aperture,z and.; a, substantially` iiatI leaf Y Spring member bridging.. said.l flattened. portion-and. biasing the ovall head.. of said pin outwardly substantiallyv transversely. away, from. said.d flattenedv portion.

GEQRGEL. ROCK.

References Cited" intha l'e.4 of this patent UNHFED; S'Pll2=.ES/.` PATENTS: 

